Robert Neville (Will Smith) is a brilliant scientist, but even he could not have stopped the spread of the terrible manmade virus. Robert is possibly the last human survivor in the world and is immune, but he is not alone. The victims have mutated into carnivorous beings who come out at night and devour anything in their path. For the last three years, Robert has spent his time scavenging for food and supplies, hiding from the infected beings, sending out radio messages to possible survivors, as well as working on an antidote for the virus using his own immune blood.